RUUD van Nistelrooy admits that the fact Sir Alex Ferguson signed an extention to his contract, played a major part in his own decision to put pen to paper on a new deal.

Ferguson's 17-year Old Trafford reign continues to be questioned in light of his legal fight with John Magnier over record-breaking racehorse Rock of Gibraltar, even though he signed a one-year rolling extension to his contract this week.

However, the Dutch striker, who put signed a £70,000-a-week deal which will keep him at Old Trafford until 2008, says the United boss has been a major influence for him.

"Sir Alex is a very important factor in this," he said. "I spoke to him about it, about the future of the club and about his plans for the team. I know that with his managerial qualities there are going to be some great years to come here and I want to be part of that."

In two-and-a-half years since making a goalscoring debut against Liverpool in the Community Shield following his £18.5m move from PSV Eindhoven in 2001, van Nistelrooy has established himself as one of the most feared frontmen in Europe.

He smashed the Champions League record for goals in a season last term, when his 44-goal seasonal tally fell just two short of Denis Law's club record.

If he became available on the open market, van Nistelrooy could name his price and his club. But once Ferguson had committed his future, there was never any question of him leaving.

The 27-year-old will never forget the debt he owes the Scot for staying loyal to him when his original United move collapsed after a failed medical.

Ferguson even invited van Nistelrooy to continue his rehabilitation at United's Carrington training ground as he recovered from the ruptured cruciate ligament he suffered in training just days after the first deal fell through.

"Ruud has proved to be a fantastic signing and his contract extension is great news for the club and the fans," said Fergie.